UTILIZATION OF SOME MUCILAGINOUS LEAVES AS BINDERS IN THE DIET OF Oreochromis niloticus FINGERLINGS

Abstract

This study evaluated the physical properties and dietary characteristics of diets with some mucilaginous leaves as binders in the diet of Oreochromis niloticus fingerlings. The three mucilaginous leaves were Abelmoschus esculentus (Okra), Corchorus olitorius (Jute Plant) and Hibiscus rosa-sinensis (Hibiscus) while corn starch was the reference binder. Quantitative and qualitative analysis of the mucilaginous leaves at different soaked for 0, 6, 8, 12, 24 hours were carried out. The viscosity of the mucilaginous leaves and that of the corn starch were carried out at these soaking durations, two temperature regimes (28 0 C and 100 0 C) and three concentrations (2, 5 and 7% w/v). The soaking durations with the highest viscosity: 0, 12 and 24 hours, were used for the preparation of three sets of diets. Twelve iso-nitrogenous diets having 35% crude protein content were formulated for each of the three experimental set-ups. Maize and wheat were added as energy sources. The diets were designated as MAI (Maize only), WHE (Wheat only), MAW (Maize and Wheat), MAC (Maize and Corchorus olitorus), WHC (Wheat and Corchorus olitorus), MWC (Maize, Wheat and Corchorus olitorus), MAH (Maize and Hibiscus rosa-sinensis), WHH (Wheat and Hibiscus rosa-sinensis), MWH (Maize, Wheat and Hibiscus rosa-sinensis), MAA (Maize and Abelmoschus esculentus), WHA (Wheat and Abelmoschus esculentus), and MWA (Maize, Wheat and Abelmoschus esculentus). Physical properties of the diets for each experimental set-up were assessed. The effects on growth during the feeding trials and the carcass composition of Oreochromis niloticus fingerling after the feeding trials were assessed for each set-up. There were significant differences (P<0.05) in the phytochemical contents: tannin, saponins, steroid, terpenoids, flavonoid and cardiac glycosides of the mucilaginous leaves for both the different soaking durations and among leaves at the same soaking duration. There were significant differences (p<0.05) in the viscosity of the mucilaginous leaves at* 2% w/v, 5% w/v, and 7% w/v at both 100 0 C and 28 0 C. There were significant differences (p<0.05) in the sinking rate, thickness swelling, water absorption index, water stability, hardness and friability of the diets in the three experimental set-ups. Diet MWH had the lowest sinking rate and crushing load, highest thickness swelling in the three experimental set-ups. Nutrient retention of diets in the three experimental set- ups were 90.70 to 95.83% for crude protein, 85.27 to 95.17% for lipid and 76.09 to 89.61% for ash. There were significant differences (p<0.05) in the mean final weight (MFW), mean weight gain (MWG), feed efficiency ratio (FER) and specific growth rate (SGR) of fish fed the diets. There were significant differences (p<0.05) in the crude protein, fat and ash content in the carcass composition of experimental fish. Survival rate for the feeding trials range between 68.89% and 100%. Results obtained established the ability of mucilaginous leaves as efficient binders for quality on-farm fish feed pellets when compared with corn starch. Any of the soaking durations for the mucilaginous leaves can be used in the preparation of quality on-farm feeds.